Hydroxy-pyrid one-monosulfonic acids

ABSTRACT

4-SUBSTITUTED-6-HYDROXY-2-PYRIDONE-5-SULFONIC ACIDS WHICH MAY BE OPTIONALLY SUBSTITUTED IN THE 1- AND 3-POSITIONS, PREPARATION THEREOF FROM THE CORRESPONDING 6-HYDROXY-2-PYRIDONE DERIVATIVES BY SULFONATION AND UTILITY THEREOF IN THE PREPARATION OF DYESTUFFS.

United States Patent Heinrich et al.

[451 Oct. 14, 1975.

HYDROXY-PYRID ONE-MONOSULFONIC ACIDS Inventors: Ernst Heinrich, Frankfurt am Main-Fechenheim; Rolf Miiller, Frankfurt am Main, both of Germany Assignee: Cassella Farbwerke Mainkur AG,

Germany Filed: July 5, 1974 Appl. No.: 485,919

Related us. Application Data Division of Ser. No. 241,845, April 6, 1972, Pat. No. 3,867,392.

Foreign Application Priority Data Apr. 10, 1971 Germany 2117753 US. Cl 260/294.8 R; 260/156; 260/247.1; 260/247.2 A; 260/2949; 260/295.5 A; 260/289 R; 8/41 A; 8/41 B Primary Examiner-Alan L. Rotman Attorney, Agent, or FirmConnolly and Hutz [57] ABSTRACT 4-substituted-6-hydroxy-2-pyridone-5-sulfonic acids which may be optionally substituted in the land 3- positions, preparation thereof from the corresponding 6-hydroxy-2-pyridone derivatives by sulfonation and utility thereof in the preparation of dyestuffs.

4 Claims, N0 Drawings 1 HYDROXY-P YRID ONE-MONOSULFONIC ACIDS CROSS-REFERENCE TO RELATED APPLICATION This application is a division of application Ser. No. 241,845 filed Apr. 6, 1972, now us. Pat. No. 3,867,392.

The present invention relates to hydroxy-pyridonemonosulfonic acids of the formula wherein X is alkyl having one to six carbon atoms; substituted alkyl wherein the alkyl moiety has from one to six carbon atoms and said substituent is selected from the group consisting of cyano, hydroxy, methoxy, amino, methylamino and dimethylamino; cyclohexyl; substituted cyclohexyl wherein said cyclohexyl substituent is selected from the group consisting of chloro, methyl and methoxy; Y is hydrogen; cyano; alkyl having one to six carbon atoms; substituted alkyl wherein the alkyl moiety has from one to six carbon atoms and said substituent is selected from the group consisting of cyano, hydroxy, methoxy, amino, methylamino and dimethylamino; cyclohexyl; substituted cyclohexyl wherein said substituent is selected from the group con- H f 0 HO N sisting of chloro, methyl and methoxy; --COR wherein ,R is amino, methylamino, dimethylamino, cyanoethyl, methoxymethyl, cyclohexyl, cyclohexylamino, alkyl having one to two carbon atoms,

or morpholino or SO R wherein R is methyl, cyclohexyl or chlorocyclohexyl; or X and Y together constitute a Cl-l )4group; and Z is hydrogen; alkyl havcyclohexyl; substituted cyclohexyl wherein the substituent is selected from the group consisting of chloro, methyl and methoxy; amino; monoalkylamino having one to four carbon atoms or dialkylamino having one to four carbon atoms, in each alkyl moiety.

The preferred compounds of the present invention are of formula I wherein X is alkyl having one to four carbon atoms, Y is hydrogen or cyano and Z is hydrogen, amino, alkyl having one to four carbon atoms, aminoalkyl having one to four carbon atoms, methylaminoalkyl wherein said alkyl has one to four carbon atoms or monoalkylamino having one to four carbon atoms. When X and Z are alkyl, they preferably have from one to two carbon atoms.

The following formulae represent the particularly preferred compounds.

CH3 C H: m s-Ki ramsfi HO 1' 0 HO I o t CH, cH,-cn,-NH,

IV V

Those skilled in the art will appreciate the fact that the hydroxy-pyridorie monosulfonic acids of formula I of the present invention may assume a variety of tauto- 50 meric forms such as illustrated by the following:

X X H 6 H035 Y 6 uo s Y N o N O r O 0 lb lc Moreover and if Z is hydrogen, a variety of tautomeric forms may exist as represented by the following:

H 1 H 8 Y id le If It is expressly understood that formula I in both the ingly substituted B-ketocarboxylic acid esters or specification and claims of the present invention, em- 10 B-ketocarbonamides. braces within its scope the tautomers thereof such as The preparation of the B-ketocarboxylic acid esters represented by the foregoing formulae. of the general formula VIII can also be done according The compounds of the present invention may be preto methods known per se, for example by acylation of pared, for example, by treating the appropriate 6- sodium aceto acetate with an'acid chloride of the genhydroxy-2-pyridone of the formula: eral formula IX:

XCO--Cl. "IX

an acid chloride of the general formula" IX in the pres ence of magnesium according to the method of M. Viswherein X, Y and Z have th above-given meanings, contini "and N. Merckling; described in 'Helvetica with sulfonating agents, preferably with chlorosulfonic Chimica Acta XXX'V, (1952) 2280-2282 whereby the acid or oleum. I compound of the general formula XI isformed which The initial compoundof the general formula may is converted into the B'ketocarbox'ylic"acid'ester of the also be present in various tautomeric forms. The initial general formula Vllla by subsequent acid cleavage, for

compounds may be prepared analogously to the example with sodium methylate in methanol'a'ccording method described by Guareschi, in "Berichte der to the method of H. Hundsdiecker described in"Be- Deutschen Chemischen Gesellschaft, Referate 29, richte der deutschen chemischen' Gesellschaft 75 Vol. 4 (1897), pages 654-656, i.e. by condensation of (1942), 454:

correspondingly substituted acetamides or acetic acid Cyanoacetamides of the general formula Vlla hydrazides of the general formula Vll with correspondingly substituted B-ketocarboxylic acid esters of the NC'CH2 CO NH- Z 'vna general formula VIII in accordance with the following reaction equatlonl 0 may be prepared according to the process of Naik and x Bhat, described in Quarterly Journ. Ind. Chem. Soc.

If a cyanoacetamide of the general formula Vlla is a CS) Y I Y condensed, for instance, with a ketocarboxylic acid ester of the general formula Vllla, a compound of the \QRZ H2011 7 0 general formula VI is obtained according to the above- I 1 given reaction scheme (a), in which Y is equal to CN 2 andlwhich is represented by the following general for- VIII Vll v| mula'VIa 1 X, Y and Z have the before mentioned meanings, R

stands for an alcyl group, in particular, the methyl or ethyl group. They may also be prepared according to H,(3 H,c| cN other methods, for instance, according to that ded H I scribed in the monograph of E. Klingsberg: Pyridine C C 'Z i and its Derivatives, Part. 3 (Interscience Publishers M N O 1962) published in the Series of Monographs The Chemistry of Heterocyclic Compounds, edited by A. Z Weissgerber or by condensation, in an alkaline mei p dium, of sulfo-acetamides or acetates with correspond- Vllla Vlla. v Vla or by 'acylation of ethyl aceto acetate' tformula X) with i are obtained.

The condensation can be effected according to the process of M.Bobbitt and D. Scola described in Journ. Org. Chem. 25 (1960) 560-560 (example 1).

cyclohexyl radical may be substituted in the manner as already indicated and which are represented hereinafter by the general formula Vld, can be obtained by condensation of a cyano acetamide of the general formula 5 Vlla with a B-ketocarboxylic acid ester which is substituted in a-position by an appropriate alkyl or cyclohexyl group and has the general formula VlIlb, analogously according to the method by M.Bobbitt and D. Scola, loc. cit. and with subsequent cleavage of the 10 cyano group in 3-position in accordance with the method by Gibson and Simonsen loc. cit. under the following reaction scheme:

X x (:=0 H,CCN

| l H,0 cu e) Y-CH c=o I HH o=c ml HO N O OH2 Z z Vlllb Vlla xn x x X Y 1 H 60% Y f) Y CN l P l C HO N 0 HO N O N o l I Z l xu Vld are obtained.

When heating to 50C compounds of the general formula Vla with an aqueous sulfuric acid of 95 the cyano group in 3-position is saponified to give a carbonamide group according to German document No. 2,045,851 laid open to public inspection and compounds of the general formula Vic CO-NH l Vlc HO N O Compounds of the general formula VI, in which Y stands for an alkyl radical bearing one to six carbon atoms or fora cyclohexyl radical, whereby the alkyl or The required a-alkyl or cyclohexyl -B-ketocarboxylic 40 acid esters are easy to prepare analogously according to the direction for the preparation of the ethyl-n-butylaceto-acetate as described in Organic Synthesis, Coll. Vol. I, 248.

Starting materials of the general formula lae XIII and XIV in glacial acetic acid using zinc chloride as condensation agent at temperatures of about to C. according the following reaction equations:

If in the above-given reaction equation (e) the cyclohexanone -2-carboxylic ethyl ester (prepared according to Organic Synthesis, Coll. Vol. II, 532) is employed as B-keto-ester component, the initial compound of the general formula VI is obtained according to the reaction equations (e) and (f), wherein X and Y constitute together a (CH group Vlg Initial compounds of the general formula VI, wherein Y stands for a CORgroup, in which R may be amino, methylamino, diethylamino, cyclohexyl amino merpholino or can also be prepared analogously in accordance with the method by U. BaSu described in Journ. Ind. Chem. Soc. 1935, 306 by condensation of a correspondingly substituted B-amino crotonic acid ester of the general formula XV with a correspondingly substituted malondiamide of the general formula XVI:

The compounds of the present invention are valuable intermediates, in particular for the preparation of dyestuffs, preferably of azo dyestuffs. In the production of azo dyes the compounds of the present invention are utilized as coupling components. The azo dyes are prepared in a manner known per se by diazotation and coupling. A diazo component is diazotized and the diazo solution is admixed with an aqueous solution that contains the sodium salt of a compound of the present invention. Coupling being terminated, the dyestuff is isolated in the usual fashion, for instance, by spraydrying. The monoazo dyes thus obtainable are suited, for example, for the dyeing and printing of cotton, wool and polyamides according to all of the convential dyeing and printing processes and yield yellow shades with good fastness properties, in particular a good fastness to light, perspiration and washing. The properties are very good, particularly where in the compounds of the present invention Y equals to hydrogen. These dyes yield, when blended with turquoise dyestuffs, very valuable, brilliant, green shades.

According to the process of the present invention these hydroxy-pyridone-monosulfonic acids contain common salt and may directly be used for the preparation of dyestuffs.

The following examples are given for the purpose of illustrating the present invention. All temperatures are given in degrees centigrade and all parts are parts by weight.

EXAMPLE 1 For the preparation of 4-methyl-6-hydroxy-2- pyridone-S-sulfonic acid, 350 parts chlorosulfonic acid are admixed at +20 +30 with parts common salt and subsequently with 63 parts 4-methyl-6-hydroxy-2- pyridone. This mixture is stirred for 4 hours at decomposed on 1,000 parts of ice and stirred for 18 hours. Subsequently, the precipitated colorless 4-methyl-6-hydroxy-2-pyridone-5-sulfonic acid is sucked off, washed on the suction apparatus with 300 parts of a common salt solution of 24 B and dried.

Analysis: C l-l,0 NS calc.: N-'-6.8% found N=5.4%

taken place. The fact that the values for the nitrogen and sulfur found are smaller than those calculated is pyridone which, as described by BOBBITT and SCOLA in .lourn. Org. Chem. 25, 560, is obtainable by condensation of ethyl aceto acetate with cyanacetamide in alcoholic alkali. It is from this product that the The 3-cyano-4-methyl-6-hydroxy-2-pyridone can be obtained as indicated in Example 1 in accordance with the method described by BOBBIT and SCOLA, loc. cit.

EXAMPLE 3 For the preparation of the l.4-dimethyl-6-hydroxy-2- pyridone-5sulfonic acid 1 l3 parts l.4-dimethyl-6- hydroxy-Z-pyridone are introduced at into 480 parts sulfuric acid monohydrate. Subsequently, at the same temperature, 90 parts oleum of 65 are alcyano group in 'P is split off with sulfuric acid. lowed to run into this mixture and stirred for 4 hours.

of 60% at 120C. in accordance with the method described by GlBSON and SIMONSEN in Journ. Chem. Soc. 1929, 1074.

EXAMPLE 2 For the preparation of the 3-cyanO-4-methyI- 6- hydroxy-2-pyridone-5-sulfonic acid, 129 parts of the monosodium salt of the 3-cyano-4-methyl-6-hydroxy- 2-pyridone are introduced at +20 +25 into 450 parts sulfonic acid monohydrate. The mixture is stirred for 1 hour, subsequently 300 parts oleum of 65 are added at the same temperature and stirring is continued for another 18 hours at +50. After cooling down to 20, the reaction batch is decomposed on 2,000 parts ice. Obtained is a limpid aqueous solution from which the colorless 3-cyano-4-methyl-6-hydroxy-2- pyridone-S-sulfonic acid being formed is separated by the introduction ofv 400 parts common salt. The reaction product is sucked off, washed on the suction apparatus with 900 parts common salt solution of 24 B and dried.

c found:

The data of the analysis (N28) show that a monosulfonation of the 3-cyano-4-methyl-6-hydroxy-2- pyridone has taken place. Due to the common salt content of the product the values for the nitrogen and sulfur found are smaller than those calculated.

The structure of the 3-cyano-4-methyl-6-hydroxy-2- pyridone-S-sulfonic acid has been confirmed by the nuclear resonance spectrum.

The 3-positioned cyano group may be split off by heating for several hours at 100 the 3-cyano-4-methyl- .6-hydroxy-2-pyridone-5-sulfonic acid in an aqueous sodium hydroxide solution of 33 Be. The reaction product obtained is identical with the 4-methyl-6-hydroxy- 2-pyridone-5-sulfonic acid obtained according to Example 1.

The sulfonation batch is then decomposed on l,800 parts of ice. After stirring for 16 hours time at room temperature, the separated colorless l.4-dimethyl-6- hydroxy-2-pyridone-5-sulfonic acid is sucked off, washed on the suction apparatus with 750 partscommon salt solution of 24 B and dried.

The data of the analysis (N:S) show that a monosulfonation of the l.4-dimethyl-6-hydroxy-2-pyridone has taken place. Due to the common salt content of the product the values for the nitrogen and sulfur found are smaller than those calculated. The structure of the 1.4- dimethyl-6-hydroxy-2-pyridone-5sulfonic acid has been confirmed by the nuclear resonance spectrum.

The following table illustrates further hydroxy pyridone-monosulfonic acids of the present invention. In the case of initial pyridones of the general formula VI which contain in one or more X-, Y and/or Z-positioned substituents a hydroxyl group, not only a sulfonation reaction takes place but also an esterification of the hydroxyl group(s). In the sulfonation, the sulfonic acid group is introduced into the pyridone nucleus. In the esterification, the OH-groups being present in the X-, Y- and/or Z-positioned substituents are converted to OSO Hgroups.

The sulfonic acid ester .groups may be split off by treating the reaction product with dilute'acids or alkalies.

Table and tautomeric forms Table Continued H0;,S Y

and tautomeric forms o N 0 thereof No X Y Z formula calc.: found:

N:S N28 74 E H CH; C H O NS l:2,28 122,31

75 CH OCH H CH C H O NS 122,28 1:226 76 CH CH CH CN -CH,CH C H O N S 111,14 l:l.l8

77 E -CN (CH CH- cwHzgoggNgs l:l.l4 1:1.16

78 CH CH CN CN CH C H O N S 110,77 1:0.75 79 CH -CH 0CH CN Cl-l C l-l O MS 121,14 l 11,16

furthermore H0 8 C H O NS 1:2,28 1:2,30

N H O H O- HO S H C H O NS 1:2,28 l:2,32

HO T o 82 no sfg C H O N S l:l,l4 l:l,l6

HO N o EXAMPLE 4 HO N 0 H is isolated by spray-drying. When applied, for instance, according to the following prescription, it yields valuable yellow prints showing in particular a good fastness to wet processing.

A fabric of mercerized or alkalized cotton is printed with the following printing paste:

50 g. of the above dyestuff 50 g. urea 425 g. hot water 450 g. alginate thickener 15 g. sodium bicarbonate l0 g. sodium salt of the m-nitrobenzene sulfonic acid The print may be fixed either by steaming at l03-105 or by thermosetting. Subsequently, the fabric is rinsed and soaped in both cases.

We claim: 'l. l-lydroxy-pyridone-monosulfonic acids of the formula and the tautomers thereof wherein X is alkyl having one to six carbon atoms; substituted alkyl wherein the alkyl moiety has from one to six carbon atoms and said substituent is selected from the group consisting of hydroxy and methoxy; cyclohexyl or substituted cyclohexyl wherein said cyclohexyl substituent is selected from the group consisting of chloro, methyl and methoxy; Y is hydrogen; alkyl having one to six carbon atoms; substituted alkyl wherein the alkyl moiety has from one to six carbon atoms and said substituent is selected from the group consisting of hydroxy and methoxy cyclohexyl; substituted cyclohexyl wherein said substituent is selected from the group consisting of chloro, methyl and methoxy or COR wherein R is methoxymethyl, cyclohexyl or alkyl having one to two carbon atoms and Z is substituted alkyl wherein the alkyl moiety has from one to six carbon atoms and said substituent is selected from the group consisting of amino, methylamino, dimethylamino and amino; monoalkylamino having one to four carbon atoms or dialkylamino having one to four carbon atoms in each alkyl moiety.

2. The hydroxy-pyridone-monosulfonic acids of claim 1 wherein X is alkyl having one to four carbon atoms, Y is hydrogen and Z is amino, aminoalkyl having one to four carbon atoms, methylaminoalkyl wherein said alkyl has from one to four carbon atoms or monoalkylamino having one to four carbon atoms.

3. The hydroxy-pyridonemonosulfonic acids of claim 2 wherein X is alkyl having one to two carbon atoms.

4. The hydroxy-pyridone-monosulfonic acids of claim 1 wherein X is methyl, Y is hydrogen and Z is aminoethyl.

UNITED STATES PATENT AND TRADEMARK OFFICE CERTIFICATE OF CORRECTION PATENT NO. 3,912,744 Page 1 of 2 DATED I October 14, 1975 INVENTO I Ernst Heinrich and Rolf Muller It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below: 4

Col. 1, lines 35-45, structural formula III should read as follows: 3

Col. 3, lines l-8, formula Ie should read as follows H H038 Y O OH line 55, "-HZOH" should read -R2OH Col. 6, lines 13-24, formula XII should read as follows:

Yl CN HO O UNITED STATES PATENT AND TRADEMARK OFFICE CERTIFICATE OF CORRECTION PATENT NO. 3,912,744 Page 2 of 2 DATED October 14, 1975 INVENTOR(S) Ernst Heinrich and Rolf Muller It is certified that errotappears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Col. 6, lines 26-38, formula VId (to the right) should read as follows:

Col. 9, line 31, "to 30" should read to Col. 11, the entry under X in Example 6, should read CH -CH -OH the entry under Y in Example 12, should read CN the "CH entry under Y between Examples 26 and 27 should not appear.

Col. 12, the entry under "found" in Example 27, should read Col. 17, line 28, a semicolon should appear aft "thoxy".

Signal and Sealed this Tenth Day of August 1976 [SEAL] Attest:

RUTH c. MASON c. MARSHALL DANN 8 ff Commissioner oj'larents and Trademarks 

1. HYDROXY-PYRIDONE-MONOSULFONIC ACIDS OF THE FORMULA
 2. The hydroxy-pyridone-monosulfonic acids of claim 1 wherein X is alkyl having one to four carbon atoms, Y is hydrogen and Z is amino, aminoalkyl having one to four carbon atoms, methylaminoalkyl wherein said alkyl has from one to four carbon atoms or monoalkylamino having one to four carbon atoms.
 3. The hydroxy-pyridone-monosulfonic acids of claim 2 wherein X is alkyl having one to two carbon atoms.
 4. The hydroxy-pyridone-monosulfonic acids of claim 1 wherein X is methyl, Y is hydrogen and Z is aminoethyl. 